Chemistry
Write "true" or "false" for the following statements:
(a) A pure substance consists of only one kind of atom or molecule. ……………
(b) The components of a mixture are present in a fixed ratio. ……………
(c) Common salt is separated from its solution in water by decantation. ……………
(d) Winnowing is a process to remove small stones from grains. ……………
(e) Gold jewellery is a homogeneous mixture of metals. ……………
(f) Air can be separated from water by filtration. ……………
(g) Salt and air dissolved in water add taste to water. ……………
(h) Steel is an alloy of iron and aluminium. ……………
Elements, Compounds & Mixtures
4 Likes
Answer
(a) True
(b) False
Correct Statement — A mixture has no fixed composition, i.e. it is formed by mixing two or more substances in any ratio without any chemical reaction.
(c) False
Correct Statement — Common salt is separated from its solution in water by evaporation
(d) False
Correct Statement — Winnowing removes lighter husk from heavier grains, whereas, small stones are removed by hand picking or sieving.
(e) True
(f) False
Correct Statement — Air can be separated from water by heating or boiling.
(g) True
(h) False
Correct Statement — Steel is an alloy of iron and carbon.
Answered By
3 Likes
Related Questions
A separating funnel is used to separate :
- miscible liquids
- sugar solution
- chalk powder and water
- immiscible liquids
Fill in the blanks :
(a) The substances that make a mixture are called its …………… or …………… .
(b) …………… is a process to separate solids dissolved in liquids.
(c) Mist is a …………… mixture of droplets of water and air.
(d) Clay is separated from water by the method of …………… .
(e) When cereals are washed before cooking, water is separated from the cereals by …………… .
(f) …………… is a process to obtain a very pure form of a solid dissolved in a liquid.
(g) Ammonium chloride can be separated from common salt by the method of …………… .
(h) The solid particles which remain on the filter paper are called …………… and the liquid which passes through it is called …………… .
(i) The process of transferring the clear liquid above the solid particles which settle at the bottom of the container is known as …………… .
(j) …………… is a method used for the separation of an insoluble solid from a solid-liquid mixture.
Match the following:
Column A Column B (a) Heterogeneous mixture (i) Homogeneous mixture (b) Evaporation (ii) Rice from husk (c) Sublimation (iii) Iron and sulphur (d) Compounds (iv) Sea Water (e) Winnowing (v) Ammonium chloride and salt Give one word for the following:
(a) The solid which is left on the filter paper after filtration.
(b) The solid particles which separate out from the solution on slow evaporation.
(c) The solid particles that settle at the bottom of the beaker in a heterogeneous mixture of a solid and a liquid.
(d) The clear liquid which is poured out after sedimentation.
(e) The technique used to separate the light particles from heavy particles using the flow of wind.